Deviations from the O3–NO–NO2 photostationary state in tropospheric chemistry

Abstract

A theoretical study of the magnitude and origin of deviations in the photostationary state relation, [Formula: see text] has been carried out by computer simulation. Various homogeneous tropospheric mixtures were chosen with initial pollutant concentrations varied from those of highly polluted to very clean atmospheres. Even for the homogeneous conditions assumed here, strong negative deviations were observed ([O3]t[NO]t/[NO2]t < (k1/k3)t for many of the conditions chosen. Failure of [I] in many cases resulted largely from the non-zero value of d[O3]/dt. Many other factors, including significant rates of O3 reaction with NO2, alkene, HO2, HO, and ozone photolysis, contribute significantly to the deviations seen in several cases considered.